A thin film transistor (TFT) is a type of field effect transistor manufactured by depositing thin films for the metallic contacts, semiconductor active layer, and dielectric layer. The channel region of a TFT is a thin film that is deposited onto a substrate. The substrate is usually glass, since an important application of TFTs is in liquid crystal displays (LCDs). Thin film transistor LCDs, a variant of LCD technology, are especially useful in cellular phone display and LCD televisions. In such devices, the TFTs are embedded within the panel itself, reducing crosstalk between pixels and improving image stability. TFT panels are also heavily used in digital radiography applications including mammography and general radiography.
Traditionally, gate induced drain leakage problems in some transistor devices are typically overcome by using spacer technology and a graded drain junction. However, in many process technologies (including some thin film technologies and printing technologies), processes for forming spacers are not readily available, and processes for forming graded junctions may be relatively complex. It may thus be advantageous to have a process for forming graded junctions that is relatively simple and/or facile to use.